gst1-plugins-base: bump to 1.20.5

- audioconvert, audioresample, audiofilter: fix divide by 0 for input buffer without caps
- cdparanoia: Ignore compiler warning coming from the cdparanoia header
- oggdemux, parsebin: More leak fixes
- opengl: fix automatic dispmanx detection for rpi4
- opengl: Fix usage of eglCreate/DestroyImage
- opengl: Fix static linking on macOS
- opusdec: Various channel-related fixes
- textrender: Negotiate caps on a GAP event if none were negotiated yet
- textrender: Don't blindly forward all events and don't blindly forward all events
- timeoverlay: fix pad leak
- oggdemux: Don't leak incoming EOS event
- subparse: Fix non-closed tag handling.
- videodecoder: Only post latency message if it changed
- videoscale: buffer meta handling fixes (NULL-terminate array of valid meta tags)
- videosink: Don't return unknown end-time from get_times()
- Bump core requirement in 1.20 branch to 1.20.4

Signed-off-by: Koen Vandeputte <koen.vandeputte@citymesh.com>